For instance, when traffic is heavy and I need to merge onto I-285, while I am still on the ramp, I pick a target vehicle that I will attempt to merge in front of. If there are driverless cars on the roadway, why would I not pick a driverless car every time? I know if I am sufficiently aggressive, the driverless vehicle’s safety programming will cause it to give way and let me in front. What happens when the three cars behind me on the ramp also take advantage of the same behavior? Suddenly the driverless car — and all the vehicles behind it — are brought to a stop while everyone cuts in front of them.
Would this happen? I don’t know about this exact scenario, but I also don’t believe we should assume drivers will treat driverless cars the same as cars with an actual person driving.
The above is only one of many potential driver behavior issues we will face as driverless cars go from a novelty to an everyday experience. Will driverless cars result in the “hassle” of driving being greatly reduced and unintentionally incentivize significantly more travel by auto? Will pedestrians and cyclists alter their behavior when interacting with driverless cars? Should driverless cars strictly follow traffic law — for example, driving 55 mph on the interstate?
Will infrastructure maintenance costs increase? Will potential congestion improvements on freeways result in congestion increases on surface streets? How does the availability of driverless vehicles transform our transit systems? Will entirely new demands not even being considered today materialize? How will the vehicle ownership model change? Who will pay for any added infrastructure costs related to driverless vehicles?
We could fill pages with questions about the potential pros and cons related to driverless cars. I believe that, while the timeline remains highly uncertain, they are likely an innovation that is unstoppable. I also believe the benefits will be many.
Overall, this technology represents a great opportunity for individuals and society. However, we must not become blind enthusiasts; we have to recognize the potential downsides. If we are proactive today in planning and building our infrastructure and creating legislation with driverless vehicles in mind, we may be able to avoid many of the potential downsides while realizing the many benefits.
Michael Hunter is an associate professor at Georgia Tech’s School of Civil and Environmental Engineering, with a focus on transportation operations and design.